A. Field of Invention
The present invention relates generally to electronic devices and specifically to a semiconductor light emitting element formed and positioned on the surface of a clear or translucent substrate providing a more efficient and even distribution of lighting and therefore improving the viewing of an item or object at night or in low light conditions. The substrate may form or be a part of protective shield, lens or cover of an object being illuminated.
B. Description of the Prior Art
Illumination is widely used in the electronic industry on products ranging from cellular telephones, calculators, watches, hand-held computers, global positioning units and gauges. Illuminating devices are also used in many other industries such as in automobiles, signs, advertising and ornamentation.
Light emitting diodes have many advantages over competing lighting elements such as electroluminescent, phosphorescent, flourescent elements as well as LCD and incandescent elements in areas such as size, cost, color variables, reliability, and power consumption.
Semiconductor light emitting diodes have been used in cellular phones, watches and other electronics but their illumination has been limited due to their positioning underneath, embedment inside a crystal or from the side of the light transmissive item receiving the illumination as described in U.S. Pat. No. 6,017,127xe2x80x94Timex, U.S. Pat. No. 3,899,871xe2x80x94Seiko, U.S. Pat. No. 4,115,994xe2x80x94Tomlinson.
Electroluminescent lighting, hereinafter referred to as EL, has been in widespread use in the electronic industry and is usually positioned underneath the item or object such as watch dials or other surfaces as described in U.S. Pat. No. 3,749,977xe2x80x94Sliker, U.S. Pat. No. 4,775,964xe2x80x94Timex, U.S. Pat. No. 4,208,869xe2x80x94Hanaoka In these references the direct illumination is provided upward towards the viewer restricting any aesthetic aspects. Another disadvantage of EL""s is that they require complicated auxiliary circuitry and limited colors to the consumer market.
Accordingly, it is an objective of the present invention to provide an improved and efficient illumination apparatus for viewing an item or object by positioning an illumination device to direct light in a direction towards the subject to be illuminated making viewing easier, more efficient and less stressful to the viewer.
A further objective of this invention is to remove the semiconductor light emitting diode packaging including the reflective directional cone and the surrounding glass or plastic protective barrier, therefore leaving the light emitting element in its raw form which when applied to the undersurface of the clear or translucent substrate radiates in a 180-degree angle and when in off mode leaves the lighting apparatus virtually invisible.
It is another objective of the present invention to provide an illumination device for electronic devices such as: cellular phones, watches, hand-held computers, global positioning units, gauges, automobiles, signs, advertising and ornamental devices eliminating any EL as the primary illumination source and its associated circuitry.
Another objective is to group semiconductor light emitting diode chips which could be red, green and blue configuration centrally or in selected areas of the substrate regulated independently by a circuit or ASICS chip with resistors limiting electrical current providing an unlimited spectrum of colors.
Another objective is to allow constant or preprogrammed illumination variables, which could be activated from a power source with a preprogrammed electronic circuit or a programmable ASICS chip and is controlled by an actuator switch, which could be within close proximity of the item or object.
These and other objects of the invention, together with features and advantages thereof will become apparent from the following detailed description of the preferred embodiment, the appended claims and the accompanying drawings.
An illuminating device is disclosed which is formed of a substrate made of a transparent, translucent or opaque. A plurality of conductors are formed on the substrate using thin film deposition techniques. The conductors may include several coextensive layers, including a layer of chromium, a layer of nicker and a layer of gold. A protective layer is then applied to cover and protect the conductors.
The device further includes one or more light emitting elements, each element being formed of semiconductor materials forming a semiconductor junctions. Importantly, no lenses are provided to concentrate light from these elements thereby insuring the light is evenly distributed as it propagates away from the device. Preferrably the light emitting element or elements are packaged in a flip chip having connecting bumps on one side. Therefore the chip can be directly connected to the conductors.
The device may be formed with several light emitting elements arranged into multicolored groups. Each group includes a red, a green and a blue element. The groups can then be activated to form a static or moving colored image.